Help about setting up a computer-based rig

Hello loopers,
I got a bit tired of the limitations of my Akay Headrush (don't ask me
why I did't participate to the survey, as I've been far from my computer
for two weeks), but I've a very limited budget.
As my girlfriend just bought a used IBM Thinkpad, I'd like to try some
computer-based looping, I'd like to set-up a system I could use live,
but my main interest now is experimenting at home.
As a musician I'm not a real computer fan, but as a computer worker, I
think I could apply a bit of my informatics experience.
I'd like to buy some flexible gear I could upgrade if I like later.
In my basic idea, I'd like to buy
- a usb audio capture device: M-audio Audiophile
- a Midi footcontroller: maybe the Behringer everybody's talking about
Apart my basses and various effects, I'll try to connect theese devices
I own:
- a behringer mixer
- a Zoom RT-123 drum machine (with only Midi-In)
- my girlfriend's Yamaha P-80 piano (with midi in, out and thru)
I'd like to receive your opinions and suggestions about this gear, Midi
connections, and first of all, about the software I could use.
I'm either a Windows user and a Linux user, but I'd prefer setting up a
Windows based system.
Thanks and sorry for my bad English
cristian